Photocatalytic hydrosilylation of conjugated dienes with triethylsilane in the presence Cr(CO)(6)

Date

1996-01-23

Author

Abdelqader, W
Chmielewski, D
Grevels, FW
Özkar, Saim
Peynircioglu, NB

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Chromium carbonyl photocatalyzed hydrosilylation of 1,3-butadiene, trans-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-butadiene, trans-2-methyl-1,3-pentadiene, and 1,3-cyclohexadiene with triethylsilane yields the cis-1,4-adducts, 1-(triethylsilyl)-2-butene derivatives, as the main products which have been isolated by distillation or preparative GC and fully characterized by NMR spectroscopy. The proposed mechanism involves the initial conversion of Cr(CO)(6) into Cr(CO)(4)(eta(4)-1,3-diene) followed by a further photolytic CO substitution by triethylsilane forming a Cr(CO)(3)(H)(SiEt(3))(eta(4)-1,3-diene) intermediate. Experiments with D-SiEt(3) lead to the conclusion that reversible addition of the hydride to the diene with formation of an eta(3)-enyl intermediate occurs prior to the irreversible silyl transfer to the organic moiety. The 1,4-hydrosilylation adduct is then replaced by new substrates to complete the catalytic cycle.

Subject Keywords

Chromium carbonyl-complexes, Group-6 metal-carbonyls, Photoinduced hydrogenation, Norbornadiene, Mechanism, Hexacarbonyl, Akenes, 1,4-hydrosilation, Hydrosilation, Substitution

URI

https://hdl.handle.net/11511/37368

Journal

ORGANOMETALLICS

DOI

https://doi.org/10.1021/om950369a

Collections

Department of Chemistry, Article

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Citation Formats

W. Abdelqader, D. Chmielewski, F. Grevels, S. Özkar, and N. Peynircioglu, “Photocatalytic hydrosilylation of conjugated dienes with triethylsilane in the presence Cr(CO)(6),” ORGANOMETALLICS, pp. 604–614, 1996, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37368.